package demo1;

public class Computer  {
    public void powerOn(){
        System.out.println("打开笔记本电脑");
    }
    public void powerOff(){
        System.out.println("关闭笔记本电脑");
    }
    public void useDevice(USB usb){
        usb.openDevice();
        if(usb instanceof Mouse ){
            Mouse mouse =(Mouse)usb;
            mouse.click();
        }else{
            keyBoard keyboard = (keyBoard) usb;
            keyboard.input();
        }
        usb.closeDevice();
    }

}
